Sinclair: marsupialia of the santa cruz beds. 
34i 
POLYPROTODONTIA. 
THYLA C YNIDAE. 
The Santa Cruz thylacynes are short-legged animals, with large heads, 
long necks and heavy tails. These characters are w r ell shown in the 
accompanying restorations of Prothylacynus patagonicus and Cladosictis 
lustratus (PI. LXI, figs. 1, 2). In order to show clearly the points oi 
Fig. 1. 
a b c d e 
Thy lacy nus cynocephalus. a , right humerus, front view ; b , right radius and ulna from the 
outer side ; r, right femur, front view ; d , right tibia, front view ; e, right fibula from the inner 
side. All figures x 
agreement between the various Patagonian genera and Thylacynus , and 
the respects in which they differ, the following summary has been intro- 
duced : 
1. In all, the facial region of the skull is short in proportion to the 
